Q: explain how practices that support diversity equality and inclusion reduce the likelihood of discrimination

A:
The theory is that by getting to know people from diverse backgrounds and ethnicity helps remove negative stereotypes. [ The problem that some people observe is that practices that cross over the line to provide preferential status to protected groups can result in less qualified people getting jobs and actually reinforcing negative stereotypes when compared to people who are fully qualified.

The solution has been to try to only implement affirmative action in cases where candidates are equally qualified, and then only until the proportion of underrepresented groups reaches the proportion found in the population itself. This reduces the risk of placing people not equipped to perform well in a job, but it retains the impression in the groups who are not protected that something other than a coin toss was used and therefore it was unfair. This perception tends to further cloud the issue.
People often cannot be objectively evaluated for all relevant aspects of job performance, and many people work in environments where their personal contact with protected groups may be limited to just a person or two. This leaves them with only anecdotal information about the benefits and effectiveness of a particular policy.
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